It depends on who you ask. Followers of Al-Qaida and ISIS deem suicide bombers, who "gave their lives for Allah" heroes, while their enemies see them as mere criminals of the worst kind imaginable (which is how I see them too). Every country has their war hero, who is controversial in the enemy country of the time the specific war took place. It always depends on who you ask.
Sometimes it can even be smaller. Some people deem Donald Trump a hero, while others deem him the worst thing that ever happened to the U.S. (I don't care in this discussion which side you are on, as that is not relevant now, my point is that there are different opinions on this matter).
I have little care for heroes, and especially people who want to be a hero. Those who want to become a hero, rarely to almost never become a true hero to me.
I do remember a recent story, where a mother with children crashed her car on a Dutch motorway. A handyman who was just underway from one customer to another saw it happening and he immediately parked on the hard shoulder, got his tools out of the back of his car and broke open the car to get the mother and her children out. The children were by miracle unharmed by the mother was in a critical condition, and we know know that if this handyman didn't act the mother would not have made it. The media branded him a "hero". He himself didn't think he deserved this honor. He said he merely had the knowledge, skills and tools to do that what he had to do to save the mother and her children's lives, and he merely felt that it was therefore his duty to use his knowledge skills and tools. Tell me... is this man a hero or is he not?
Of course, for this handyman there were little risks to hurt himself. He knew his stuff as a handyman. Somebody who runs into a burning house to save a child's life, does risk their own. Does that make them a hero where this handyman may not be?
If I must define "hero" it comes to "somebody who goes beyond himself, despite the risks to do that what is right", that is the best definition, but also a vague one. What is "right"? That is also different from where you stand. And there is no human without a fault and that includes "heroes", and having heroic deeds on your name does not justify criminal actions, and that is also something we quite often like to forget. The good never erases the bad and vice versa.
I think the term "hero" is therefore nothing more, but rubbish.